The teacher will be very surprised to see your correct solution 😉
x = -2*1^1/5
x1 = -2
/ ___________ ___________\ ___ | / ___ / ___ | 1 \/ 5 | / 5 \/ 5 ___ / 5 \/ 5 | x2 = - - ----- + I*|- / - - ----- - \/ 5 * / - - ----- | 2 2 \ \/ 8 8 \/ 8 8 /
/ ___________ ___________ ___________ ___________\ | / ___ / ___ / ___ / ___ | | / 5 \/ 5 / 5 \/ 5 ___ / 5 \/ 5 ___ / 5 \/ 5 | ___________ ___________ | / - - ----- / - + ----- \/ 5 * / - - ----- \/ 5 * / - + ----- | / ___ / ___ 1 | \/ 8 8 \/ 8 8 \/ 8 8 \/ 8 8 | / 5 \/ 5 / 5 \/ 5 x3 = - + I*|- ---------------- - ---------------- + ---------------------- - ----------------------| + 2* / - - ----- * / - + ----- 2 \ 2 2 2 2 / \/ 8 8 \/ 8 8
/ ___________ ___________ ___________ ___________\ | / ___ / ___ / ___ / ___ | | / 5 \/ 5 / 5 \/ 5 ___ / 5 \/ 5 ___ / 5 \/ 5 | ___________ ___________ | / - + ----- / - - ----- \/ 5 * / - - ----- \/ 5 * / - + ----- | / ___ / ___ 1 |\/ 8 8 \/ 8 8 \/ 8 8 \/ 8 8 | / 5 \/ 5 / 5 \/ 5 x4 = - + I*|---------------- - ---------------- + ---------------------- + ----------------------| - 2* / - - ----- * / - + ----- 2 \ 2 2 2 2 / \/ 8 8 \/ 8 8
___________ ___ / ___ 1 \/ 5 / 5 \/ 5 x5 = - + ----- + 2*I* / - - ----- 2 2 \/ 8 8
sum
/ ___________ ___________ ___________ ___________\ / ___________ ___________ ___________ ___________\ | / ___ / ___ / ___ / ___ | | / ___ / ___ / ___ / ___ | / ___________ ___________\ | / 5 \/ 5 / 5 \/ 5 ___ / 5 \/ 5 ___ / 5 \/ 5 | ___________ ___________ | / 5 \/ 5 / 5 \/ 5 ___ / 5 \/ 5 ___ / 5 \/ 5 | ___________ ___________ ___________ ___ | / ___ / ___ | | / - - ----- / - + ----- \/ 5 * / - - ----- \/ 5 * / - + ----- | / ___ / ___ | / - + ----- / - - ----- \/ 5 * / - - ----- \/ 5 * / - + ----- | / ___ / ___ ___ / ___ 1 \/ 5 | / 5 \/ 5 ___ / 5 \/ 5 | 1 | \/ 8 8 \/ 8 8 \/ 8 8 \/ 8 8 | / 5 \/ 5 / 5 \/ 5 1 |\/ 8 8 \/ 8 8 \/ 8 8 \/ 8 8 | / 5 \/ 5 / 5 \/ 5 1 \/ 5 / 5 \/ 5 0 - 2 + - - ----- + I*|- / - - ----- - \/ 5 * / - - ----- | + - + I*|- ---------------- - ---------------- + ---------------------- - ----------------------| + 2* / - - ----- * / - + ----- + - + I*|---------------- - ---------------- + ---------------------- + ----------------------| - 2* / - - ----- * / - + ----- + - + ----- + 2*I* / - - ----- 2 2 \ \/ 8 8 \/ 8 8 / 2 \ 2 2 2 2 / \/ 8 8 \/ 8 8 2 \ 2 2 2 2 / \/ 8 8 \/ 8 8 2 2 \/ 8 8
=
/ ___________ ___________ ___________ ___________\ / ___________ ___________ ___________ ___________\ | / ___ / ___ / ___ / ___ | | / ___ / ___ / ___ / ___ | / ___________ ___________\ | / 5 \/ 5 / 5 \/ 5 ___ / 5 \/ 5 ___ / 5 \/ 5 | | / 5 \/ 5 / 5 \/ 5 ___ / 5 \/ 5 ___ / 5 \/ 5 | ___________ | / ___ / ___ | | / - + ----- / - - ----- \/ 5 * / - - ----- \/ 5 * / - + ----- | | / - - ----- / - + ----- \/ 5 * / - - ----- \/ 5 * / - + ----- | / ___ | / 5 \/ 5 ___ / 5 \/ 5 | |\/ 8 8 \/ 8 8 \/ 8 8 \/ 8 8 | | \/ 8 8 \/ 8 8 \/ 8 8 \/ 8 8 | / 5 \/ 5 I*|- / - - ----- - \/ 5 * / - - ----- | + I*|---------------- - ---------------- + ---------------------- + ----------------------| + I*|- ---------------- - ---------------- + ---------------------- - ----------------------| + 2*I* / - - ----- \ \/ 8 8 \/ 8 8 / \ 2 2 2 2 / \ 2 2 2 2 / \/ 8 8
product
/ / ___________ ___________ ___________ ___________\ \ / / ___________ ___________ ___________ ___________\ \ | | / ___ / ___ / ___ / ___ | | | | / ___ / ___ / ___ / ___ | | / / ___________ ___________\\ | | / 5 \/ 5 / 5 \/ 5 ___ / 5 \/ 5 ___ / 5 \/ 5 | ___________ ___________| | | / 5 \/ 5 / 5 \/ 5 ___ / 5 \/ 5 ___ / 5 \/ 5 | ___________ ___________| / ___________\ | ___ | / ___ / ___ || | | / - - ----- / - + ----- \/ 5 * / - - ----- \/ 5 * / - + ----- | / ___ / ___ | | | / - + ----- / - - ----- \/ 5 * / - - ----- \/ 5 * / - + ----- | / ___ / ___ | | ___ / ___ | |1 \/ 5 | / 5 \/ 5 ___ / 5 \/ 5 || |1 | \/ 8 8 \/ 8 8 \/ 8 8 \/ 8 8 | / 5 \/ 5 / 5 \/ 5 | |1 |\/ 8 8 \/ 8 8 \/ 8 8 \/ 8 8 | / 5 \/ 5 / 5 \/ 5 | |1 \/ 5 / 5 \/ 5 | 1*-2*|- - ----- + I*|- / - - ----- - \/ 5 * / - - ----- ||*|- + I*|- ---------------- - ---------------- + ---------------------- - ----------------------| + 2* / - - ----- * / - + ----- |*|- + I*|---------------- - ---------------- + ---------------------- + ----------------------| - 2* / - - ----- * / - + ----- |*|- + ----- + 2*I* / - - ----- | \2 2 \ \/ 8 8 \/ 8 8 // \2 \ 2 2 2 2 / \/ 8 8 \/ 8 8 / \2 \ 2 2 2 2 / \/ 8 8 \/ 8 8 / \2 2 \/ 8 8 /
=
_______________ ______________ / ___ _______________ / ___ I*\/ 50 - 10*\/ 5 / ___ 5*I*\/ 10 - 2*\/ 5 -32 + -------------------- - I*\/ 50 + 10*\/ 5 + --------------------- 2 2
-32 + i*sqrt(50 - 10*sqrt(5))/2 - i*sqrt(50 + 10*sqrt(5)) + 5*i*sqrt(10 - 2*sqrt(5))/2
x1 = 1.61803398874989 + 1.17557050458495*i
x2 = -2.0
x3 = -0.618033988749895 - 1.90211303259031*i
x4 = -0.618033988749895 + 1.90211303259031*i
x5 = 1.61803398874989 - 1.17557050458495*i
x5 = 1.61803398874989 - 1.17557050458495*i